In my opinion, there are two themes to this poem. First, the poem is telling us that we people tend to think that the grass is always greener on the other side of the fence. We think that other people's situations are better than our own. Second, the poem is telling us that we cannot really know the minds and hearts of other people (at least not if we do not know them intimately).

Personally, I can relate to the idea of wanting to be like other people. For example, I played volleyball and basketball in high school and so I always wished I were taller and skinnier. I wished that my balance of brain to athletic talent had tipped more towards the talent side... I cannot identify, however, with the idea that someone can seem to "have it all" yet be that sad. I have never been in that position.

The poem "Richard Cory" by Edward Arlington Robinson is about two types of isolation: isolation from others, and isolation from physical comfort. Written in 1897, Robinson's poem recalls the economic depression when the citizens of America had to subsist on bread, often day-old bread. These are the people "on the pavement" who work and "curse the bread" in their miserable lives. They view Richard Cory, who is above them socially, as almost royalty:

He was a gentleman from sole to crown,

Clean favored, and imperially slim.

But, he, too, is discontented, for he ventures into town and speaks to people--"Good morning"--but no one talks with him; instead, he is perceived as glittering like a king and watched with envy:

In fine, we thought that he was everything

To make us wish that we were in his place.

Sadly, the people's envy is unjustified as Richard Cory is desperately lonely, so lonely that he kills himself. It seems that social isolation is the greater burden.

Sarah Margaret Ferguson, the Duchess of York, wrote how lonely it was when she was married to Prince Andrew. She was confined to one floor of Windsor castle with little lighting, and could only come to other rooms at certain times. Much like Richard Cory, she was isolated from the communion of others, one of the basic needs of all humans beings. Hers is not an unusual situation for those who are wealthy and famous.